POTENTIAL EFFECTS OF CLIMATE CHANGE ON AGRICULTURAL WATER USE IN THE SOUTHEAST U.S.1

ABSTRACT: Climate change has the potential to have dramatic effects on the agricultural sector nationally and internationally as documented in many research papers. This paper reports on research that was focused on a specific crop growing area to demonstrate how farm managers might respond to climate-induced yield changes and the implications of these responses for agricultural water use. The Hadley model was used to generate climate scenarios for important agricultural areas of Georgia in 2030 and 2090. Linked crop response models indicated generally positive yield changes, as increased temperatures were associated with increased precipitation and CO2. Using a farm management model, differences in climate-induced yield impacts among crops led to changes in crop mix and associated water use; non-irrigated cropland received greater benefit since irrigated land was already receiving adequate moisture. Model results suggest that farm managers will increase cropping intensity by decreasing fallowing and increasing double cropping; corn acreage decreased dramatically, peanuts decreased moderately and cotton and winter wheat increased. Water use on currently irrigated cropland fell. The potential for increased water use through conversion of agriculturally important, but currently non-irrigated, growing areas is substantial.     

Managing United States Public Lands in Response to Climate Change: A View From the Ground Up

Federal land managers are faced with the task of balancing multiple uses and goals when making decisions about land use and the activities that occur on public lands. Though climate change is now well recognized by federal agencies and their local land and resource managers, it is not yet clear how issues related to climate change will be incorporated into on-the-ground decision making within the framework of multiple use objectives. We conducted a case study of a federal land management agency field office, the San Juan Public Lands Center in Durango, CO, U.S.A., to understand from their perspective how decisions are currently made, and how climate change and carbon management are being factored into decision making. We evaluated three major management sectors in which climate change or carbon management may intersect other use goals: forests, biofuels, and grazing. While land managers are aware of climate change and eager to understand more about how it might affect land resources, the incorporation of climate change considerations into everyday decision making is currently quite limited. Climate change is therefore on the radar screen, but remains a lower priority than other issues. To assist the office in making decisions that are based on sound scientific information, further research is needed into how management activities influence carbon storage and resilience of the landscape under climate change.     

Pragmatic Approaches for Water Management Under Climate Change Uncertainty1

Stakhiv, Eugene Z., 2011. Pragmatic Approaches for Water Management Under Climate Change Uncertainty. Journal of the American Water Resources Association (JAWRA) 47(6):1183–1196. DOI: 10.1111/j.1752‐1688.2011.00589.x Abstract: Water resources management is in a difficult transition phase, trying to accommodate large uncertainties associated with climate change while struggling to implement a difficult set of principles and institutional changes associated with integrated water resources management. Water management is the principal medium through which projected impacts of global warming will be felt and ameliorated. Many standard hydrological practices, based on assumptions of a stationary climate, can be extended to accommodate numerous aspects of climate uncertainty. Classical engineering risk and reliability strategies developed by the water management profession to cope with contemporary climate uncertainties can also be effectively employed during this transition period, while a new family of hydrological tools and better climate change models are developed. An expansion of the concept of “robust decision making,” coupled with existing analytical tools and techniques, is the basis for a new approach advocated for planning and designing water resources infrastructure under climate uncertainty. Ultimately, it is not the tools and methods that need to be revamped as much as the suite of decision rules and evaluation principles used for project justification. They need to be aligned to be more compatible with the implications of a highly uncertain future climate trajectory, so that the hydrologic effects of that uncertainty are correctly reflected in the design of water infrastructure.     

Potential CO2 Emission Reduction by Development of Non-Grain-Based Bioethanol in China

Assessment of the potential CO₂ emission reduction by development of non-grain-based ethanol in China is valuable for both setting up countermeasures against climate change and formulating bioethanol policies. Based on the land occupation property, feedstock classification and selection are conducted, identifying sweet sorghum, cassava, and sweet potato as plantation feedstocks cultivated from low-quality arable marginal land resources and molasses and agricultural straws as nonplantation feedstocks derived from agricultural by-products. The feedstock utilization degree, CO₂ reduction coefficient of bioethanol, and assessment model of CO₂ emission reduction potential of bioethanol are proposed and established to assess the potential CO₂ emission reduction by development of non-grain-based bioethanol. The results show that China can obtain emission reduction potentials of 10.947 and 49.027 Mt CO₂ with non-grain-based bioethanol in 2015 and 2030, which are much higher than the present capacity, calculated as 1.95 Mt. It is found that nonplantation feedstock can produce more bioethanol so as to obtain a higher potential than plantation feedstock in both 2015 and 2030. Another finding is that developing non-grain-based bioethanol can make only a limited contribution to China’s greenhouse gas emission reduction. Moreover, this study reveals that the regions with low and very low potentials for emission reduction will dominate the spatial distribution in 2015, and regions with high and very high potentials will be the majority in 2030.     

东北地区典型农区土地利用变化对农业扩张和气候变化的响应研究

大规模的农业扩张和全球气候变化导致东北地区发生剧烈的土地利用/土地覆盖变化。本研究分析了研究区1976—2008年的土地利用变化和生长季各月气温的变化趋势,并结合农业扩张程度,探究LUCC对农业扩张和气候变化的响应,为指导农业发展规划和保障国家粮食安全提供理论依据。结果表明,1976—2008年农田面积逐步增加,生长季气温一直呈上升趋势。1976—2001年生长季气温的上升趋势不稳定,气温变化程度较大;2001—2008年,农业扩张放缓,生长季气温上升趋势显著,且上升趋势一直增加,气温变化比上一时期更稳定;且这两个时期农业扩张和气候变化对土地利用强度的影响在南北和东西方向上均存在明显差异。     

Exploring changes in Ecuadorian land use for food production and their effects on natural resources

A model is used for the dynamic and spatially explicit exploration of near future agricultural land-use changes. In a case study for Ecuador, different plausible scenarios are formulated, taking into account possible developments in national food demand until the year 2010. The protection of nature parks and restrictions due to land degradation are evaluated with respect to their possible spatial impacts on the land-use change dynamics within the country. Under the assumptions of the demand scenarios, agricultural land-use expands significantly, resulting in more use of land in existing agricultural areas and frontier-type expansion into relatively undisturbed natural areas. The patterns of change depend on the increase in demand, competition between land-use types, changes in driving factors of land use, and the area and characteristics of land that is excluded from agricultural use. The modelled land-use dynamics are related to their possible impacts on the natural resource base, specifically soil fertility. The results indicate potential negative effects of land-use changes on the soil nutrient balance and biodiversity. It is argued that spatial and temporal quantification of land-use dynamics at the landscape level can support research and policies aimed at understanding the driving factors of land-use change and the behaviour of complex agro-ecosystems under changing conditions at different scales. In this way, issues dealing with sustainable food production and the management of the natural resource base can be addressed in a more integrated and quantitative manner.     

Sensitivity Analysis of Best Management Practices Under Climate Change Scenarios1

Woznicki, Sean A. and A. Pouyan Nejadhashemi, 2011. Sensitivity Analysis of Best Management Practices Under Climate Change Scenarios. Journal of the American Water Resources Association (JAWRA) 48(1): 90‐112. DOI: 10.1111/j.1752‐1688.2011.00598.x Abstract: Understanding the sensitivity of best management practices (BMPs) implementation as climate changes will be important for water resources management. The objective of this study was to determine how the sensitivity of BMPs performance vary due to changes in precipitation, temperature, and CO₂ using the Soil and Water Assessment Tool. Sediment, total nitrogen, and total phosphorus loads on an annual and monthly basis were estimated before and after implementation of eight agricultural BMPs for different climate scenarios. Downscaled climate change data were obtained from the National Center for Atmospheric Research Community Climate System Model for the Tuttle Creek Lake watershed in Kansas and Nebraska. Using a relative sensitivity index, native grass, grazing management, and filter strips were determined to be the most sensitive for all climate change scenarios, whereas porous gully plugs, no‐tillage, and conservation tillage were the least sensitive on an annual basis. The monthly sensitivity analysis revealed that BMP sensitivity varies largely on a seasonal basis for all climate change scenarios. The results of this research suggest that the majority of agricultural BMPs tested in this study are significantly sensitive to climate change. Therefore, caution should be exercised in the decision‐making processes.     

Nigeria’s Response to the Impacts of Climate Change: Developing Resilient and Ethical Adaptation Options

Global climate change will have a strong impact on Nigeria, particularly on agricultural production and associated livelihoods. Although there is a growing scientific consensus about the impact of climate change, efforts so far in Nigeria to deal with these impacts are still rudimentary and not properly coordinated. There is little evidence of any pragmatic approach towards tracking climate change in order to develop an evidence base on which to formulate national adaptation strategies. Although Nigeria is not alone in this regard, the paper asserts that National Climate Change Adaptation Strategy could help address this situation by guiding the integration of climate change adaptation into government policies, strategies, and programs, with particular focus on the most vulnerable groups and the agricultural sectors. There is an urgent need to adopt abatement strategies that will provide economic incentives to reduce the risk from disasters, such as developing agricultural practices that are more resilient to a changing climate.     

Integrated urban water management modelling under climate change scenarios

The concept of integrated water management is uncommon in urban areas, unless there is a shortage of supply and severe conflicts among the users competing for limited water resources. Further, problem of water management in urban areas will aggravate due to uncertain climatic events. Therefore, an Integrated Urban Water Management Model considering Climate Change (IUWMCC) has been presented which is suitable for optimum allocation of water from multiple sources to satisfy the demands of different users under different climate change scenarios. Effect of climate change has been incorporated in non-linear mathematical model of resource allocation in term of climate change factors. These factors have been developed using runoff responses corresponding to base and future scenario of climate. Future scenarios have been simulated using stochastic weather generator (LARS-WG) for different IPCC climate change scenarios i.e. A1B, A2 and B1. Further, application of model has been demonstrated for a realistic water supply system of Ajmer urban fringe (India). Developed model is capable in developing adaptation strategies for optimum water resources planning and utilization in urban areas under different climate change scenarios.     

Linking climate policy across economic sectors: A case for green growth in Nepal

While the energy sector is the largest global contributor to greenhouse gas (GHG) emissions, the agriculture, forestry, and other land use (AFOLU) sector account for up to 80% of GHG emissions in the least developed countries (LDCs). Despite this, the nationally determined contributions (NDCs) of LDCs, including Nepal, focus primarily on climate mitigation in the energy sector. This paper introduces green growth—a way to foster economic growth while ensuring access to resources and environmental services—as an approach to improving climate policy coherence across sectors. Using Nepal as a case country, this study models the anticipated changes in resource use and GHG emissions between 2015 and 2030, that would result from implementing climate mitigation actions in Nepal's NDC. The model uses four different scenarios. They link NDC and policies across economic sectors and offer policy insights regarding (1) energy losses that could cost up to 10% of gross domestic product (GDP) by 2030, (2) protection of forest resources by reducing the use of biomass fuels from 465 million gigajoules (GJ) in 2015 to 195 million GJ in 2030, and (3) a significant reduction in GHG emissions by 2030 relative to the business-as-usual (BAU) case by greater use of electricity from hydropower rather than biomass. These policy insights are significant for Nepal and other LDCs as they seek an energy transition towards using more renewable energy and electricity.     

A Decision‐Analytic Approach to Managing Climate Risks: Application to the Upper Great Lakes1

Brown, Casey, William Werick, Wendy Leger, and David Fay, 2011. A Decision‐Analytic Approach to Managing Climate Risks: Application to the Upper Great Lakes. Journal of the American Water Resources Association (JAWRA) 47(3):524‐534. DOI: 10.1111/j.1752‐1688.2011.00552.x Abstract: In this paper, we present a risk analysis and management process designed for use in water resources planning and management under climate change. The process incorporates climate information through a method called decision‐scaling, whereby information related to climate projections is tailored for use in a decision‐analytic framework. The climate risk management process begins with the identification of vulnerabilities by asking stakeholders and resource experts what water conditions they could cope with and which would require substantial policy or investment shifts. The identified vulnerabilities and thresholds are formalized with a water resources systems model that relates changes in the physical climate conditions to the performance metrics corresponding to vulnerabilities. The irreducible uncertainty of climate change projections is addressed through a dynamic management plan embedded within an adaptive management process. Implementation of the process is described as applied in the ongoing International Upper Great Lakes Study.     

Trade-off analysis in the Northern Andes to study the dynamics in agricultural land use

In this paper we hypothesize that land use change can be induced by non-linearities and thresholds in production systems that impact farmers' decision making. Tradeoffs between environmental and economic indicators is a useful way to represent dynamic properties of agricultural systems. The Tradeoff Analysis (TOA) System is software designed to implement the integrated analysis of tradeoffs in agricultural systems. The TOA methodology is based on spatially explicit econometric simulation models linked to spatially referenced bio-physical simulation models to simulate land use and input decisions. The methodology has been applied for the potato-pasture production system in the Ecuadorian Andes. The land use change literature often describes non-linearity in land use change as a result of sudden changes in the political (e.g. new agricultural policies) or environmental setting (e.g. earthquakes). However, less attention has been paid to the non-linearities in production systems and their consequences for land use change. In this paper, we use the TOA system to study agricultural land use dynamics and to find the underlying processes for non-linearities. Results show that the sources of non-linearities are in the properties of bio-physical processes and in the decision making-process of farmers.     

DEVELOPMENT AND MANAGEMENT OF LAND/WATER RESOURCES: THE EVERGLADES,AGRICULTURE, AND SOUTH FLORIDA1

ABSTRACT: South Florida and the Everglades have been under intensive development since 1850 by Federal and State governments who encouraged and financed extensive drainage and hydraulic changes, primarily for agricultural settlement. Agricultural development of the sugar industry in the northern Everglades adjacent to Lake Okeechobee rapidly progressed only after the 1900s. Political and resource management conflicts have arisen because policies which once favored development are now being reversed by policies and regulation efforts to restore and conserve natural ecosystems. Currently, the environmental and ecological impacts of agricultural land use adjacent to natural wtlands of the Everglades are being assessed. The objectives of this paper are: (1) to outline the historical development of south Florida and the sugar industry, (2) to relate this history to political and management policy changes occurring as it pertains to ecosystem restoration and the multiuser competition for water/land resources, and (3) to propose how integrated resource management might be utilized for a sustainable Everglades and south Florida. This paper outlines the historical paradox of urban settlement, land development, and agricultural production, with efforts in the recent decade to acquire, manage, and preserve land and water resources for natural areas conservation. Only though the use of integrated resource management will the defined resource conflicts be mediated.     

Incorporating Climate Change Into Water Resources Planning in England and Wales1

Arnell, Nigel W., 2011. Incorporating Climate Change Into Water Resources Planning in England and Wales. Journal of the American Water Resources Association (JAWRA) 47(3):541‐549. DOI: 10.1111/j.1752‐1688.2011.00548.x Abstract: Public water supplies in England and Wales are provided by around 25 private‐sector companies, regulated by an economic regulator (Ofwat) and environmental regulator (Environment Agency). As part of the regulatory process, companies are required periodically to review their investment needs to maintain safe and secure supplies, and this involves an assessment of the future balance between water supply and demand. The water industry and regulators have developed an agreed set of procedures for this assessment. Climate change has been incorporated into these procedures since the late 1990s, although has been included increasingly seriously over time and it has been an effective legal requirement to consider climate change since the 2003 Water Act. In the most recent assessment in 2009, companies were required explicitly to plan for a defined amount of climate change, taking into account climate change uncertainty. A “medium” climate change scenario was defined, together with “wet” and “dry” extremes, based on scenarios developed from a number of climate models. The water industry and its regulators are now gearing up to exploit the new UKCP09 probabilistic climate change projections – but these pose significant practical and conceptual challenges. This paper outlines how the procedures for incorporating climate change information into water resources planning have evolved, and explores the issues currently facing the industry in adapting to climate change.     

Downscaling climate change scenarios in an urban land use change model

The objective of this paper is to describe the process through which climate change scenarios were downscaled in an urban land use model and the results of this experimentation. The land use models (Urban Growth Model [UGM] and the Land Cover Deltatron Model [LCDM]) utilized in the project are part of the SLEUTH program which uses a probabilistic cellular automata protocol. The land use change scenario experiments were developed for the 31-county New York Metropolitan Region (NYMR) of the US Mid-Atlantic Region. The Intergovernmental Panel on Climate Change (IPCC), regional greenhouse gas (GHG) emissions scenarios (Special Report on Emissions Scenarios (SRES) A2 and B2 scenarios) were used to define the narrative scenario conditions of future land use change. The specific research objectives of the land use modeling work involving the SLEUTH program were threefold: (1) Define the projected conversion probabilities and the amount of rural-to-urban land use change for the NYMR as derived by the UGM and LCDM for the years 2020 and 2050, as defined by the pattern of growth for the years 1960-1990; (2) Down-scale the IPCC SRES A2 and B2 scenarios as a narrative that could be translated into alternative growth projections; and, (3) Create two alternative future growth scenarios: A2 scenario which will be associated with more rapid land conversion than found in initial projections, and a B2 scenario which will be associated with a slower level of land conversion. The results of the modeling experiments successfully illustrate the spectrum of possible land use/land cover change scenarios for the years 2020 and 2050. The application of these results into the broader scale climate and health impact study is discussed, as is the general role of land use/land cover change models in climate change studies and associated environmental management strategies.     

Context-dependent evaluation of climate change policies: competing policies,knowledge and emotions

Climate change policies can compete with policies on other social and environmental problems for limited economic resources. This paper investigates the potential influence of alternative policies on citizens’ preferences for climate change policies. A contingent valuation study was implemented to estimate the impact of observable and unobservable contextual effects of competing polices on climate change valuation. Individuals are also investigated about their endowment of knowledge and emotional reactions to such problems. The results show that citizens’ valuation of climate change policies crucially depends on the context-dependent competing policies. The valuation rises as the number of competing policies increases. This increment becomes economically significant when the competing policies are related to specific problems such as forest fires and development. In addition, the valuation also rises with the amount of knowledge endowed by the individual about the climate change problem, and with the experience of negative emotions such as fear and sadness.     

Effects of climate and land use changes on groundwater resources in coastal aquifers

To estimate the freshwater loss in coastal aquifers due to salinisation, a numerical model based on the sharp interface assumption has been introduced. The developed methodology will be useful in areas where limited hydrological data are available. This model will elaborate on the changes in fresh groundwater loss with respect to climate change, land use pattern and hydrologic soil condition. The aridity index has been introduced to represent the variations in precipitation and temperature. The interesting finding is that the deforestation leads to increase groundwater recharge in arid areas, because deforestation leads to reduce evapotranspiration even though it favors runoff. The combined climate and land use scenarios show that when the aridity index is less than 60, the agricultural lands give higher groundwater recharge than other land use patterns for all hydrologic soil conditions. The calculated recharge was then used to estimate the freshwater-saltwater interface and percentage of freshwater loss due to salinity intrusion. We found that in arid areas, the fresh groundwater loss increases as the percentage of forest cover increases. The combined effects of deforestation and aridity index on fresh groundwater loss show that deforestation causes an increase in the recharge and existing fresh groundwater resource in areas having low precipitation and high temperature (arid climates).     

Adapting to Climate Change at the Local Level: The Spatial Planning Response

Climate change is a major issue for all levels of government, global, national and local. Local authorities' responses to climate change have tended to concentrate on their role in reducing greenhouse gases. However, the scientific consensus is that we also need to adapt to unavoidable climate change. Spatial planning at a local level has a critical anticipatory role to play in promoting robust adaptation. This paper reviews the shift in local authorities' planning policies for climate change adaptation in the UK since 2000, and provides evidence of underlying attitudes amongst planning professionals to climate change. It shows that, while the issue of climate change is becoming recognized with respect to flood risk, the wider implications (for instance, for biodiversity and water resources) are not yet integrated into plans. The reasons for this lie in lack of political support and lack of engagement of the planning profession with climate change networks. But the paper also argues there are difficulties in acknowledging the need for adaptation at the local level, with the short-term horizons of local plans at odds with perceptions of the long-term implications of climate change.     

From climate change impacts to adaptation: A development perspective for India

India has good reasons to be concerned about climate change as it could adversely affect the achievement of vital national development goals related to socio‐economic development, human welfare, health, energy availability and use, and infrastructure. The paper attempts to develop a framework for integrated impact assessment and adaptation responses, using a recently built railroad coastal infrastructure asset in India as an example. The framework links climate change variables — temperature, rainfall, sea level rise, extreme events, and other secondary variables — and sustainable development variables — technology, institutions, economic, and other policies. The study indicates that sustainable development variables generally reduce the adverse impacts on the system due to climate change alone, except when they are inadequately applied. The paper concludes that development is a vital variable for integrated impact assessment. Well crafted developmental policies could result in a less‐GHG intensive future, enhanced adaptive capacities of communities and systems, and lower impacts due to climate change.     

Food Security in the Face of Climate Change,Population Growth,and Resource Constraints: Implications for Bangladesh

Ensuring food security has been one of the major national priorities of Bangladesh since its independence in 1971. Now, this national priority is facing new challenges from the possible impacts of climate change in addition to the already existing threats from rapid population growth, declining availability of cultivable land, and inadequate access to water in the dry season. In this backdrop, this paper has examined the nature and magnitude of these threats for the benchmark years of 2030 and 2050. It has been shown that the overall impact of climate change on the production of food grains in Bangladesh would probably be small in 2030. This is due to the strong positive impact of CO₂ fertilization that would compensate for the negative impacts of higher temperature and sea level rise. In 2050, the negative impacts of climate change might become noticeable: production of rice and wheat might drop by 8% and 32%, respectively. However, rice would be less affected by climate change compared to wheat, which is more sensitive to a change in temperature. Based on the population projections and analysis of future agronomic innovations, this study further shows that the availability of cultivable land alone would not be a constraint for achieving food self-sufficiency, provided that the productivity of rice and wheat grows at a rate of 10% or more per decade. However, the situation would be more critical in terms of water availability. If the dry season water availability does not decline from the 1990 level of about 100 Bm³, there would be just enough water in 2030 for meeting both the agricultural and nonagricultural needs. In 2050, the demand for irrigation water to maintain food self-sufficiency would be about 40% to 50% of the dry season water availability. Meeting such a high agricultural water demand might cause significant negative impacts on the domestic and commercial water supply, fisheries, ecosystems, navigation, and salinity management.